Long-term care residents often experience sleep disturbances as they are vulnerable to a variety of physical, psychosocial, and environmental factors that contribute to sleep disturbances. However, few studies have examined the combined impact of multiple factors on sleep among long-term care residents. This study aimed to identify the factors that influence sleep efficiency and sleep quality based on a modified senescent sleep model. A total of 125 residents were recruited from seven long-term care facilities in South Korea. Sleep patterns and sleep quality were collected using 3-day sleep logs and the Minimal Insomnia Screening Scale for Korean adults (KMISS), respectively. The mean sleep efficiency was 84.6% and the mean score on sleep quality was 15.25. A multiple linear regression analysis showed that greater dependence in activities of daily living (ADL), higher pain, and light at night were related to lower sleep efficiency. Higher pain and fatigue, less activity time, noise and light at night, and lower nighttime staffing levels were related to poorer sleep quality. This study highlights that psychosocial and environmental factors as well as physical factors could influence sleep for long-term care residents. Our findings could be foundational evidence for multi-faceted sleep intervention program development in long-term care settings.

Wildlife watching is an emerging ecotourism activity around the world. In Australia and New Zealand, night viewing of little penguins attracts hundreds of thousands of visitors per year. As penguins start coming ashore after sunset, artificial lighting is essential to allow visitors to view them in the dark. This alteration of the nightscape warrants investigation for any potential effects of artificial lighting on penguin behavior. We experimentally tested how penguins respond to different light wavelengths (colors) and intensities to examine effects on the colony attendance behavior at two sites on Phillip Island, Australia. At one site, nocturnal artificial illumination has been used for penguin viewing for decades, whereas at the other site, the only light is from the natural night sky. Light intensity did not affect colony attendance behaviors of penguins at the artificially lit site, probably due to penguin habituation to lights. At the not previously lit site, penguins preferred lit paths over dark paths to reach their nests. Thus, artificial light might enhance penguin vision at night and consequently it might reduce predation risk and energetic costs of locomotion through obstacle and path detection. Although penguins are faithful to their path, they can be drawn to artificial lights at small spatial scale, so light pollution could attract penguins to undesirable lit areas. When artificial lighting is required, we recommend keeping lighting as dim and time-restricted as possible to mitigate any negative effects on the behavior of penguins and their natural habitat.

The effects of light on health can be divided into three sections. The first is that of light as radiation. Exposure to the ultraviolet, visible, and infrared radiation produced by light sources can damage both the eye and skin, through both thermal and photochemical mechanisms. Such damage is rare for indoor lighting installations designed for vision but can occur in some situations. The second is light operating through the visual system. Lighting enables us to see but lighting conditions that cause visual discomfort are likely to lead to eyestrain. Anyone who frequently experiences eyestrain is not enjoying the best of health. The lighting conditions that cause visual discomfort in buildings are well known and easily avoided. The third is light operating through the circadian system. This is known to influence sleep patterns and believed to be linked to the development of breast cancer among night shift workers. There is still much to learn about the impact of light on human health but what is known is enough to ensure that the topic requires the attention of all those concerned with the lighting of buildings.

The recognition of vision as a powerful register for organising urban space locates lighting technologies at the heart of urban experience. Recently, scholars have established that lighting technologies shape not just what we see but how we see, drawing attention towards light as that ‘with which we see’. This article shifts attention from the role of lighting in shaping what and how people see, to how people make sense of changes to their visual sensorium—from what lighting infrastructures do to what is done with them. By following older residents living in the London Borough of Newham along routine travels on foot at night, I demonstrate how they make sense of the Council’s initiative to upgrade their 19,500 street-lamps with Light Emitting Diodes. I demonstrate how such infrastructural change exposes an uneven geographical distribution of and access to light and darkness with potentially detrimental consequences for the formation of public life after dark. Recognising how light infrastructures are reframed through everyday life, I demonstrate how LEDs do not necessarily produce their desired effects and how light clutter and light bleed might contribute to producing nocturnal atmospheres where people feel safe and confident. Broadening the understanding of how different technologies and light sources are important for the formation of inclusive nocturnal publics the article sets out a ‘politics of visibility’ that recognises the role of lighting in creating visibility for and of residents.

The alternation of light and dark rhythm causes a series of physiological, biochemical and metabolic changes in animals, which also alters the growth and development of animals, and feeding, migration, reproduction and other behavioral activities. In recent years, many studies have reported the effects of long-term (more than 6 weeks) illumination on ovarian growth and development. In this study, we observed the damage, repair and apoptosis of ovarian DNA in a short period of illumination. The results showed that, in short time (less than 2 weeks) illumination conditions, the 24 hrs-light treatment caused the reduction of total ovarian follicle number and downregulation of circadian clock related genes. Furthermore, the changed levels of serum sex hormones were also detected after 24 hrs-light exposure, of which the concentrations of LH (luteinizing hormone), FSH (follicle-stimulating hormone) and E2 (estradiol) were increased, but the concentration of PROG (progesterone) was decreased. Moreover, 24 hrs-light exposure increased the expression of DNA damage and repair related genes, the number of TUNEL and RAD51 positive cells. These results indicated that 24 hrs-light exposure for 4 days, 8days and 12 days increased DNA damage and cell apoptosis, thereby affecting the development of ovary.